Alexis Sanchez - Arsenal
The second-largest transfer in Arsenal's history, with an estimated £32 million fee, Arsene Wenger pulled off a major coup in bringing the Chile star to the Emirates Stadium from Barcelona.
Deemed surplus to requirements at Camp Nou ahead of Luis Suarez's arrival, Alexis turned down Liverpool to join Arsenal.
He was a key player in his country's run to the last 16 of the World Cup, and Arsenal fans will be hoping the fleet-of-foot forward can help fire them to a first Premier League title since 2004.
Diego Costa - Chelsea
After his haul of 36 goals in all competitions helped Atletico Madrid to the Spanish title and the UEFA Champions League final, Chelsea decided to splash over £30m on Costa.
Jose Mourinho regularly bemoaned his striking options as Chelsea finished third in the Premier League last term, and he will hope Spain international Costa gives his team a goalscoring threat they lacked in 2013-14.
And Costa certainly knows how to find the net, having scored more goals than Chelsea's three frontline strikers - Fernando Torres, Samuel Eto'o and Demba Ba - managed between them last season.
Cesc Fabregas - Chelsea
Another man Mourinho feels can take Chelsea to the next level, former Arsenal captain Fabregas has arrived at Stamford Bridge for a fee thought to be around £27m.
After a frustrating three-year stint at boyhood club Barcelona - who he re-joined from Arsenal in 2011 - Fabregas, 27, is sure to be determined to once again take the Premier League by storm.
Mourinho has earmarked Fabregas as the player to replace the huge influence of Chelsea legend Frank Lampard in his midfield.
If he can do just that, as well as clicking with Costa, the Stamford Bridge club will not be far away from winning the league.
Adam Lallana - Liverpool
A graceful and skilful playmaker, Lallana was the driving force behind Southampton's superb Premier League season last term.
Lallana's form earned him a spot in England's World Cup squad, and a big-money move to Liverpool - where he will supplement the likes of Philippe Coutinho and Raheem Sterling as the Merseyside club look to go one better than their runners-up spot in 2013-14.
Romelu Lukaku - Everton
Lukaku was outstanding for Everton last season, with his 15 Premier League goals while on loan from Chelsea helping Roberto Martinez to a fifth-place finish in his maiden campaign in charge at Goodison Park.
Indeed, Martinez was so impressed by the Belgium international, he decided to smash Everton's transfer record to bring him to Merseyside permanently in a deal worth £28m.
Qualification for the Champions League represents Everton's goal this season - and Lukaku is key to their chances of achieving that objective.
Eliaquim Mangala - Manchester City
City may have won the Premier League last season, but there were several occasions where they looked vulnerable at the back.
And that is the reason manager Manuel Pellegrini has decided to spend a reported £42.9m to bring France international Mangala to the Etihad Stadium from Porto.
A strong, domineering centre-back, the 23-year-old will be deployed alongside captain Vincent Kompany at the heart of City's backline.
Dejan Lovren - Liverpool
A porous defence represented Liverpool's undoing in their unlikely challenge for last season's title.
Brendan Rodgers' men were lethal going forward - scoring 101 goals - but conceded 13 more than City, who eventually beat them to the crown by two points.
Rodgers has been seeking a vocal defensive leader since the retirement of Jamie Carragher and, in Lovren, believes he has found his man.
At a reported fee of £20m from Southampton, the Croatia international did not come cheap.
But if Lovren can shore up Liverpool's backline sufficiently to go one better in the Premier League this season, he will be worth every penny.
Ander Herrera - Manchester United
United, then managed by David Moyes, tried to sign Herrera on transfer deadline day last year.
That move failed, but, 12 months on, United have finally got their man by landing the deep-lying midfielder from Athletic Bilbao for a fee just shy of £30m.
A typically Spanish midfielder - all touch, technique and passing ability - Herrera will likely slot into new boss Louis van Gaal's engine room alongside Michael Carrick when the England international returns from an ankle injury.
Luke Shaw - Manchester United
Another newcomer in the Van Gaal revolution at Old Trafford, United made Shaw the most expensive teenager in football when they paid Southampton around £30m for the full-back's services in June.
The 19-year-old - like Lallana and Lovren - was a huge part of Southampton's success last term, and Van Gaal will hope he fills the void left by the departing Patrice Evra.
Bojan Krkic - Stoke City
Once considered to be a worthy contemporary of Lionel Messi after coming through Barcelona's renowned youth system, Bojan has lost his way somewhat in recent years.
Unfulfilling loan spells at Milan, Roma and Ajax have come and gone, but the 23-year-old will hope to find a home at Stoke after completing arguably the transfer window's most intriguing move so far last month.
The diminutive forward hit the ground running in pre-season, scoring three goals in three appearances, and manager Mark Hughes will be hoping he translates that form into the Premier League.
